Modulation type: CW
Exposure duration: repeated daily exposure, 3 x 20 min/day at 4-h intervals, for 7 days
|Chamber||The exposure chamber [Donnellan et al., 1997] consisted of a cubic aluminium box of 1.1 m internal side length and contained a horizontal loop antenna mounted on a horizontal Masonite shelf located at the mid point of the chamber. The reflective walls formed a resonant chamber, and thus a complex modal field pattern was generated that was taken into account in the experimental design.|
|Setup||Cells in 20 ml of culture medium in a 75-cm² flask were placed in the exposure chamber.|
|Sham exposure||A sham exposure was conducted.|
|Additional info||The cells were allowed to cool during the exposure. After 20 min, there was less than 1°C difference between the temperature of the culture medium in the exposed (26.5°C) and sham (25.8°C) flasks, and this difference occurred only during the last 5 min of the exposure.|
There was no significant morphological difference between the control HMC-1 cells and the exposed cells. There was a consistent trend for an increase in the amount of immunoreactive protein kinase C in the membrane fraction of the exposed cells and a concomitant decrease in the cytosolic fraction. Reproducible and significant changes in expression were seen in only three out of a total of 588 genes screened. The results provide evidence that low-level microwave exposure can affect both gene expression and molecules involved in important cell regulatory functions.